Installation of local developed extension via pip not recognized as JupyterLab extension

I am further my JupyterLab extension jupyterlab-hide-cells:

I am developing in a conda environment:

  • JupyterLab 3.2.0
  • Python 3.11.0
  • node v.18.13.0
  • Hatch, version 1.7.0
  • twine version 4.0.2 (importlib-metadata: 5.2.0, keyring: 24.2.0, pkginfo: 1.10.0, requests: 2.28.2, requests-toolbelt: 1.0.0, urllib3: 1.26.14)

So I followed the instruction in RELEASE.md:

hatch version 3.0.1
jlpm clean:all
python -m build
pip install dist/jupyterlab_hide_cells-3.0.1-py3-none-any.whl

Installation was first successfull, but it was not installed as a JupyterLab Extension (not listed in jupyter labextension list). I also started JupyterLab, but the features are not existing.

Similar problem exist when installing extension locally directly via pip install -e ".".

Installing the extension locally via:

jlpm
jlpm build
jupyter labextension install .

on the other hand works.

9 months before I was able to publish the package via pip and install it also via pip (see PyP: jupyterlab-hide-cells · PyPI).

Does anyone has an idea what I did wrong?

An annotation: I compared the new and the old tar.gz and I saw that in the new one the init.py is missing